CD274 and breast carcinoma: RT has emerged as a front-runner strategy, where previous studies using murine models of breast cancer showed that it can convert tumors to become responsive to immune checkpoint therapy [156, 157] Interestingly, Azad and coworkers [158] reported that PD-L1 was upregulated after RT and chemotherapy in a JAK/STAT dependent manner, while the intratumoral milieu was shifted away from infiltration of immunosuppressive MDSCs and Tregs towards the infiltration of activated CD8+ cells.